A laser toner cartridge contains a few significant components that directly affect the print quality and durability over time. These significant components are all located in the development section of the cartridge. The above mentioned components are the photosensitive drum that is made of an electrically conducting material such as aluminum, the developing roller, the regulating member and the primary charge roller.
During operation of a laser printer the photosensitive drum rotates as its drive gear is rotated. Specific models of cartridges are known to have specific gear designs. Also, such gears are typically attached to the drum by mechanical techniques, such as described in U.S. Pat. No. 7,248,841, where a mechanical crimping and coupling process was used.
The coating on the photosensitive drum typically wears off after one lifecycle of the cartridge as a result of constant friction between the photosensitive component and the primary charge roller, as well as friction between the developing roller and the printed media. The amount of wear depends on multiple factors such as: type of media printed, average coverage area of the printed documents, type of toner used, type of documents printed (short: 1-2 pages or long: 100+pages) type of coating etc. It was found out that more often than not using the same photosensitive drum for another or second lifecycle, would not produce the same print quality as the original cartridge over the whole second lifecycle of the remanufactured cartridge. Therefore, in conventional remanufacturing processes the photosensitive drum is treated as an exhausted component and is replaced by a new one on all known remanufactured models of cartridges.
While the photosensitive drum can become exhausted during a single lifecycle, the drum's drive gear typically does not become exhausted with such use, and can be re-used. In addition, the original drum's drive gear, or specific features of a drum's drive gear may be the subject of one or more patents, such as for example the particular shape of a drive gear that is unique to a certain product line. In order to reuse a cartridge component conventionally considered to be not reusable, as a precaution in order to avoid possible patent infringement claims and as a way to reduce costs of remanufacturing a toner cartridge, a need exists for a process and associated apparatus by which the drive gear of original equipment toner cartridge photosensitive drums may be reused.